// This file is part of Eigen, a lightweight C++ template library
// for linear algebra.
//
// Copyright (C) 2010 Gael Guennebaud <gael.guennebaud@inria.fr>
// Copyright (C) 2016 Konstantinos Margaritis <markos@freevec.org>
//
// This Source Code Form is subject to the terms of the Mozilla
// Public License v. 2.0. If a copy of the MPL was not distributed
// with this file, You can obtain one at http://mozilla.org/MPL/2.0/.

#ifndef EIGEN_COMPLEX32_ALTIVEC_H
#define EIGEN_COMPLEX32_ALTIVEC_H

namespace Eigen {

namespace internal {

#if !defined(__ARCH__) || (defined(__ARCH__) && __ARCH__ >= 12)
static Packet4ui p4ui_CONJ_XOR = { 0x00000000,
								   0x80000000,
								   0x00000000,
								   0x80000000 }; // vec_mergeh((Packet4ui)p4i_ZERO, (Packet4ui)p4f_MZERO);
#endif

static Packet2ul p2ul_CONJ_XOR1 =
	(Packet2ul)vec_sld((Packet4ui)p2d_ZERO_, (Packet4ui)p2l_ZERO, 8); //{ 0x8000000000000000, 0x0000000000000000 };
static Packet2ul p2ul_CONJ_XOR2 =
	(Packet2ul)vec_sld((Packet4ui)p2l_ZERO, (Packet4ui)p2d_ZERO_, 8); //{ 0x8000000000000000, 0x0000000000000000 };

struct Packet1cd
{
	EIGEN_STRONG_INLINE Packet1cd() {}
	EIGEN_STRONG_INLINE explicit Packet1cd(const Packet2d& a)
		: v(a)
	{
	}
	Packet2d v;
};

struct Packet2cf
{
	EIGEN_STRONG_INLINE Packet2cf() {}
	EIGEN_STRONG_INLINE explicit Packet2cf(const Packet4f& a)
		: v(a)
	{
	}
#if !defined(__ARCH__) || (defined(__ARCH__) && __ARCH__ < 12)
	union
	{
		Packet4f v;
		Packet1cd cd[2];
	};
#else
	Packet4f v;
#endif
};

template<>
struct packet_traits<std::complex<float>> : default_packet_traits
{
	typedef Packet2cf type;
	typedef Packet2cf half;
	enum
	{
		Vectorizable = 1,
		AlignedOnScalar = 1,
		size = 2,
		HasHalfPacket = 0,

		HasAdd = 1,
		HasSub = 1,
		HasMul = 1,
		HasDiv = 1,
		HasNegate = 1,
		HasAbs = 0,
		HasAbs2 = 0,
		HasMin = 0,
		HasMax = 0,
		HasBlend = 1,
		HasSetLinear = 0
	};
};

template<>
struct packet_traits<std::complex<double>> : default_packet_traits
{
	typedef Packet1cd type;
	typedef Packet1cd half;
	enum
	{
		Vectorizable = 1,
		AlignedOnScalar = 1,
		size = 1,
		HasHalfPacket = 0,

		HasAdd = 1,
		HasSub = 1,
		HasMul = 1,
		HasDiv = 1,
		HasNegate = 1,
		HasAbs = 0,
		HasAbs2 = 0,
		HasMin = 0,
		HasMax = 0,
		HasSetLinear = 0
	};
};

template<>
struct unpacket_traits<Packet2cf>
{
	typedef std::complex<float> type;
	enum
	{
		size = 2,
		alignment = Aligned16,
		vectorizable = true,
		masked_load_available = false,
		masked_store_available = false
	};
	typedef Packet2cf half;
};
template<>
struct unpacket_traits<Packet1cd>
{
	typedef std::complex<double> type;
	enum
	{
		size = 1,
		alignment = Aligned16,
		vectorizable = true,
		masked_load_available = false,
		masked_store_available = false
	};
	typedef Packet1cd half;
};

/* Forward declaration */
EIGEN_STRONG_INLINE void
ptranspose(PacketBlock<Packet2cf, 2>& kernel);

/* complex<double> first */
template<>
EIGEN_STRONG_INLINE Packet1cd
pload<Packet1cd>(const std::complex<double>* from)
{
	EIGEN_DEBUG_ALIGNED_LOAD return Packet1cd(pload<Packet2d>((const double*)from));
}
template<>
EIGEN_STRONG_INLINE Packet1cd
ploadu<Packet1cd>(const std::complex<double>* from)
{
	EIGEN_DEBUG_UNALIGNED_LOAD return Packet1cd(ploadu<Packet2d>((const double*)from));
}
template<>
EIGEN_STRONG_INLINE void
pstore<std::complex<double>>(std::complex<double>* to, const Packet1cd& from)
{
	EIGEN_DEBUG_ALIGNED_STORE pstore((double*)to, from.v);
}
template<>
EIGEN_STRONG_INLINE void
pstoreu<std::complex<double>>(std::complex<double>* to, const Packet1cd& from)
{
	EIGEN_DEBUG_UNALIGNED_STORE pstoreu((double*)to, from.v);
}

template<>
EIGEN_STRONG_INLINE Packet1cd
pset1<Packet1cd>(const std::complex<double>& from)
{ /* here we really have to use unaligned loads :( */
	return ploadu<Packet1cd>(&from);
}

template<>
EIGEN_DEVICE_FUNC inline Packet1cd
pgather<std::complex<double>, Packet1cd>(const std::complex<double>* from, Index stride EIGEN_UNUSED)
{
	return pload<Packet1cd>(from);
}
template<>
EIGEN_DEVICE_FUNC inline void
pscatter<std::complex<double>, Packet1cd>(std::complex<double>* to, const Packet1cd& from, Index stride EIGEN_UNUSED)
{
	pstore<std::complex<double>>(to, from);
}
template<>
EIGEN_STRONG_INLINE Packet1cd
padd<Packet1cd>(const Packet1cd& a, const Packet1cd& b)
{
	return Packet1cd(a.v + b.v);
}
template<>
EIGEN_STRONG_INLINE Packet1cd
psub<Packet1cd>(const Packet1cd& a, const Packet1cd& b)
{
	return Packet1cd(a.v - b.v);
}
template<>
EIGEN_STRONG_INLINE Packet1cd
pnegate(const Packet1cd& a)
{
	return Packet1cd(pnegate(Packet2d(a.v)));
}
template<>
EIGEN_STRONG_INLINE Packet1cd
pconj(const Packet1cd& a)
{
	return Packet1cd((Packet2d)vec_xor((Packet2d)a.v, (Packet2d)p2ul_CONJ_XOR2));
}
template<>
EIGEN_STRONG_INLINE Packet1cd
pmul<Packet1cd>(const Packet1cd& a, const Packet1cd& b)
{
	Packet2d a_re, a_im, v1, v2;

	// Permute and multiply the real parts of a and b
	a_re = vec_perm(a.v, a.v, p16uc_PSET64_HI);
	// Get the imaginary parts of a
	a_im = vec_perm(a.v, a.v, p16uc_PSET64_LO);
	// multiply a_re * b
	v1 = vec_madd(a_re, b.v, p2d_ZERO);
	// multiply a_im * b and get the conjugate result
	v2 = vec_madd(a_im, b.v, p2d_ZERO);
	v2 = (Packet2d)vec_sld((Packet4ui)v2, (Packet4ui)v2, 8);
	v2 = (Packet2d)vec_xor((Packet2d)v2, (Packet2d)p2ul_CONJ_XOR1);

	return Packet1cd(v1 + v2);
}
template<>
EIGEN_STRONG_INLINE Packet1cd
pand<Packet1cd>(const Packet1cd& a, const Packet1cd& b)
{
	return Packet1cd(vec_and(a.v, b.v));
}
template<>
EIGEN_STRONG_INLINE Packet1cd
por<Packet1cd>(const Packet1cd& a, const Packet1cd& b)
{
	return Packet1cd(vec_or(a.v, b.v));
}
template<>
EIGEN_STRONG_INLINE Packet1cd
pxor<Packet1cd>(const Packet1cd& a, const Packet1cd& b)
{
	return Packet1cd(vec_xor(a.v, b.v));
}
template<>
EIGEN_STRONG_INLINE Packet1cd
pandnot<Packet1cd>(const Packet1cd& a, const Packet1cd& b)
{
	return Packet1cd(vec_and(a.v, vec_nor(b.v, b.v)));
}
template<>
EIGEN_STRONG_INLINE Packet1cd
ploaddup<Packet1cd>(const std::complex<double>* from)
{
	return pset1<Packet1cd>(*from);
}
template<>
EIGEN_STRONG_INLINE Packet1cd
pcmp_eq(const Packet1cd& a, const Packet1cd& b)
{
	Packet2d eq = vec_cmpeq(a.v, b.v);
	Packet2d tmp = { eq[1], eq[0] };
	return (Packet1cd)pand<Packet2d>(eq, tmp);
}

template<>
EIGEN_STRONG_INLINE void
prefetch<std::complex<double>>(const std::complex<double>* addr)
{
	EIGEN_ZVECTOR_PREFETCH(addr);
}

template<>
EIGEN_STRONG_INLINE std::complex<double>
pfirst<Packet1cd>(const Packet1cd& a)
{
	std::complex<double> EIGEN_ALIGN16 res;
	pstore<std::complex<double>>(&res, a);

	return res;
}

template<>
EIGEN_STRONG_INLINE Packet1cd
preverse(const Packet1cd& a)
{
	return a;
}
template<>
EIGEN_STRONG_INLINE std::complex<double>
predux<Packet1cd>(const Packet1cd& a)
{
	return pfirst(a);
}
template<>
EIGEN_STRONG_INLINE std::complex<double>
predux_mul<Packet1cd>(const Packet1cd& a)
{
	return pfirst(a);
}
EIGEN_MAKE_CONJ_HELPER_CPLX_REAL(Packet1cd, Packet2d)

template<>
EIGEN_STRONG_INLINE Packet1cd
pdiv<Packet1cd>(const Packet1cd& a, const Packet1cd& b)
{
	// TODO optimize it for AltiVec
	Packet1cd res = pmul(a, pconj(b));
	Packet2d s = vec_madd(b.v, b.v, p2d_ZERO_);
	return Packet1cd(pdiv(res.v, s + vec_perm(s, s, p16uc_REVERSE64)));
}

EIGEN_STRONG_INLINE Packet1cd pcplxflip /*<Packet1cd>*/ (const Packet1cd& x)
{
	return Packet1cd(preverse(Packet2d(x.v)));
}

EIGEN_STRONG_INLINE void
ptranspose(PacketBlock<Packet1cd, 2>& kernel)
{
	Packet2d tmp = vec_perm(kernel.packet[0].v, kernel.packet[1].v, p16uc_TRANSPOSE64_HI);
	kernel.packet[1].v = vec_perm(kernel.packet[0].v, kernel.packet[1].v, p16uc_TRANSPOSE64_LO);
	kernel.packet[0].v = tmp;
}

/* complex<float> follows */
template<>
EIGEN_STRONG_INLINE Packet2cf
pload<Packet2cf>(const std::complex<float>* from)
{
	EIGEN_DEBUG_ALIGNED_LOAD return Packet2cf(pload<Packet4f>((const float*)from));
}
template<>
EIGEN_STRONG_INLINE Packet2cf
ploadu<Packet2cf>(const std::complex<float>* from)
{
	EIGEN_DEBUG_UNALIGNED_LOAD return Packet2cf(ploadu<Packet4f>((const float*)from));
}
template<>
EIGEN_STRONG_INLINE void
pstore<std::complex<float>>(std::complex<float>* to, const Packet2cf& from)
{
	EIGEN_DEBUG_ALIGNED_STORE pstore((float*)to, from.v);
}
template<>
EIGEN_STRONG_INLINE void
pstoreu<std::complex<float>>(std::complex<float>* to, const Packet2cf& from)
{
	EIGEN_DEBUG_UNALIGNED_STORE pstoreu((float*)to, from.v);
}

template<>
EIGEN_STRONG_INLINE std::complex<float>
pfirst<Packet2cf>(const Packet2cf& a)
{
	std::complex<float> EIGEN_ALIGN16 res[2];
	pstore<std::complex<float>>(res, a);

	return res[0];
}

#if !defined(__ARCH__) || (defined(__ARCH__) && __ARCH__ < 12)
template<>
EIGEN_STRONG_INLINE Packet2cf
pset1<Packet2cf>(const std::complex<float>& from)
{
	Packet2cf res;
	res.cd[0] = Packet1cd(vec_ld2f((const float*)&from));
	res.cd[1] = res.cd[0];
	return res;
}
#else
template<>
EIGEN_STRONG_INLINE Packet2cf
pset1<Packet2cf>(const std::complex<float>& from)
{
	Packet2cf res;
	if ((std::ptrdiff_t(&from) % 16) == 0)
		res.v = pload<Packet4f>((const float*)&from);
	else
		res.v = ploadu<Packet4f>((const float*)&from);
	res.v = vec_perm(res.v, res.v, p16uc_PSET64_HI);
	return res;
}
#endif

template<>
EIGEN_DEVICE_FUNC inline Packet2cf
pgather<std::complex<float>, Packet2cf>(const std::complex<float>* from, Index stride)
{
	std::complex<float> EIGEN_ALIGN16 af[2];
	af[0] = from[0 * stride];
	af[1] = from[1 * stride];
	return pload<Packet2cf>(af);
}
template<>
EIGEN_DEVICE_FUNC inline void
pscatter<std::complex<float>, Packet2cf>(std::complex<float>* to, const Packet2cf& from, Index stride)
{
	std::complex<float> EIGEN_ALIGN16 af[2];
	pstore<std::complex<float>>((std::complex<float>*)af, from);
	to[0 * stride] = af[0];
	to[1 * stride] = af[1];
}

template<>
EIGEN_STRONG_INLINE Packet2cf
padd<Packet2cf>(const Packet2cf& a, const Packet2cf& b)
{
	return Packet2cf(padd<Packet4f>(a.v, b.v));
}
template<>
EIGEN_STRONG_INLINE Packet2cf
psub<Packet2cf>(const Packet2cf& a, const Packet2cf& b)
{
	return Packet2cf(psub<Packet4f>(a.v, b.v));
}
template<>
EIGEN_STRONG_INLINE Packet2cf
pnegate(const Packet2cf& a)
{
	return Packet2cf(pnegate(Packet4f(a.v)));
}

template<>
EIGEN_STRONG_INLINE Packet2cf
pand<Packet2cf>(const Packet2cf& a, const Packet2cf& b)
{
	return Packet2cf(pand<Packet4f>(a.v, b.v));
}
template<>
EIGEN_STRONG_INLINE Packet2cf
por<Packet2cf>(const Packet2cf& a, const Packet2cf& b)
{
	return Packet2cf(por<Packet4f>(a.v, b.v));
}
template<>
EIGEN_STRONG_INLINE Packet2cf
pxor<Packet2cf>(const Packet2cf& a, const Packet2cf& b)
{
	return Packet2cf(pxor<Packet4f>(a.v, b.v));
}
template<>
EIGEN_STRONG_INLINE Packet2cf
pandnot<Packet2cf>(const Packet2cf& a, const Packet2cf& b)
{
	return Packet2cf(pandnot<Packet4f>(a.v, b.v));
}

template<>
EIGEN_STRONG_INLINE Packet2cf
ploaddup<Packet2cf>(const std::complex<float>* from)
{
	return pset1<Packet2cf>(*from);
}

template<>
EIGEN_STRONG_INLINE void
prefetch<std::complex<float>>(const std::complex<float>* addr)
{
	EIGEN_ZVECTOR_PREFETCH(addr);
}

#if !defined(__ARCH__) || (defined(__ARCH__) && __ARCH__ < 12)

template<>
EIGEN_STRONG_INLINE Packet2cf
pcmp_eq(const Packet2cf& a, const Packet2cf& b)
{
	Packet4f eq = pcmp_eq<Packet4f>(a.v, b.v);
	Packet2cf res;
	Packet2d tmp1 = { eq.v4f[0][1], eq.v4f[0][0] };
	Packet2d tmp2 = { eq.v4f[1][1], eq.v4f[1][0] };
	res.v.v4f[0] = pand<Packet2d>(eq.v4f[0], tmp1);
	res.v.v4f[1] = pand<Packet2d>(eq.v4f[1], tmp2);
	return res;
}

template<>
EIGEN_STRONG_INLINE Packet2cf
pconj(const Packet2cf& a)
{
	Packet2cf res;
	res.v.v4f[0] = pconj(Packet1cd(reinterpret_cast<Packet2d>(a.v.v4f[0]))).v;
	res.v.v4f[1] = pconj(Packet1cd(reinterpret_cast<Packet2d>(a.v.v4f[1]))).v;
	return res;
}

template<>
EIGEN_STRONG_INLINE Packet2cf
pmul<Packet2cf>(const Packet2cf& a, const Packet2cf& b)
{
	Packet2cf res;
	res.v.v4f[0] =
		pmul(Packet1cd(reinterpret_cast<Packet2d>(a.v.v4f[0])), Packet1cd(reinterpret_cast<Packet2d>(b.v.v4f[0]))).v;
	res.v.v4f[1] =
		pmul(Packet1cd(reinterpret_cast<Packet2d>(a.v.v4f[1])), Packet1cd(reinterpret_cast<Packet2d>(b.v.v4f[1]))).v;
	return res;
}

template<>
EIGEN_STRONG_INLINE Packet2cf
preverse(const Packet2cf& a)
{
	Packet2cf res;
	res.cd[0] = a.cd[1];
	res.cd[1] = a.cd[0];
	return res;
}

template<>
EIGEN_STRONG_INLINE std::complex<float>
predux<Packet2cf>(const Packet2cf& a)
{
	std::complex<float> res;
	Packet1cd b = padd<Packet1cd>(a.cd[0], a.cd[1]);
	vec_st2f(b.v, (float*)&res);
	return res;
}

template<>
EIGEN_STRONG_INLINE std::complex<float>
predux_mul<Packet2cf>(const Packet2cf& a)
{
	std::complex<float> res;
	Packet1cd b = pmul<Packet1cd>(a.cd[0], a.cd[1]);
	vec_st2f(b.v, (float*)&res);
	return res;
}

EIGEN_MAKE_CONJ_HELPER_CPLX_REAL(Packet2cf, Packet4f)

template<>
EIGEN_STRONG_INLINE Packet2cf
pdiv<Packet2cf>(const Packet2cf& a, const Packet2cf& b)
{
	// TODO optimize it for AltiVec
	Packet2cf res;
	res.cd[0] = pdiv<Packet1cd>(a.cd[0], b.cd[0]);
	res.cd[1] = pdiv<Packet1cd>(a.cd[1], b.cd[1]);
	return res;
}

EIGEN_STRONG_INLINE Packet2cf pcplxflip /*<Packet2cf>*/ (const Packet2cf& x)
{
	Packet2cf res;
	res.cd[0] = pcplxflip(x.cd[0]);
	res.cd[1] = pcplxflip(x.cd[1]);
	return res;
}

EIGEN_STRONG_INLINE void
ptranspose(PacketBlock<Packet2cf, 2>& kernel)
{
	Packet1cd tmp = kernel.packet[0].cd[1];
	kernel.packet[0].cd[1] = kernel.packet[1].cd[0];
	kernel.packet[1].cd[0] = tmp;
}

template<>
EIGEN_STRONG_INLINE Packet2cf
pblend(const Selector<2>& ifPacket, const Packet2cf& thenPacket, const Packet2cf& elsePacket)
{
	Packet2cf result;
	const Selector<4> ifPacket4 = { ifPacket.select[0], ifPacket.select[0], ifPacket.select[1], ifPacket.select[1] };
	result.v = pblend<Packet4f>(ifPacket4, thenPacket.v, elsePacket.v);
	return result;
}
#else
template<>
EIGEN_STRONG_INLINE Packet2cf
pcmp_eq(const Packet2cf& a, const Packet2cf& b)
{
	Packet4f eq = vec_cmpeq(a.v, b.v);
	Packet4f tmp = { eq[1], eq[0], eq[3], eq[2] };
	return (Packet2cf)pand<Packet4f>(eq, tmp);
}
template<>
EIGEN_STRONG_INLINE Packet2cf
pconj(const Packet2cf& a)
{
	return Packet2cf(pxor<Packet4f>(a.v, reinterpret_cast<Packet4f>(p4ui_CONJ_XOR)));
}
template<>
EIGEN_STRONG_INLINE Packet2cf
pmul<Packet2cf>(const Packet2cf& a, const Packet2cf& b)
{
	Packet4f a_re, a_im, prod, prod_im;

	// Permute and multiply the real parts of a and b
	a_re = vec_perm(a.v, a.v, p16uc_PSET32_WODD);

	// Get the imaginary parts of a
	a_im = vec_perm(a.v, a.v, p16uc_PSET32_WEVEN);

	// multiply a_im * b and get the conjugate result
	prod_im = a_im * b.v;
	prod_im = pxor<Packet4f>(prod_im, reinterpret_cast<Packet4f>(p4ui_CONJ_XOR));
	// permute back to a proper order
	prod_im = vec_perm(prod_im, prod_im, p16uc_COMPLEX32_REV);

	// multiply a_re * b, add prod_im
	prod = pmadd<Packet4f>(a_re, b.v, prod_im);

	return Packet2cf(prod);
}

template<>
EIGEN_STRONG_INLINE Packet2cf
preverse(const Packet2cf& a)
{
	Packet4f rev_a;
	rev_a = vec_perm(a.v, a.v, p16uc_COMPLEX32_REV2);
	return Packet2cf(rev_a);
}

template<>
EIGEN_STRONG_INLINE std::complex<float>
predux<Packet2cf>(const Packet2cf& a)
{
	Packet4f b;
	b = vec_sld(a.v, a.v, 8);
	b = padd<Packet4f>(a.v, b);
	return pfirst<Packet2cf>(Packet2cf(b));
}

template<>
EIGEN_STRONG_INLINE std::complex<float>
predux_mul<Packet2cf>(const Packet2cf& a)
{
	Packet4f b;
	Packet2cf prod;
	b = vec_sld(a.v, a.v, 8);
	prod = pmul<Packet2cf>(a, Packet2cf(b));

	return pfirst<Packet2cf>(prod);
}

EIGEN_MAKE_CONJ_HELPER_CPLX_REAL(Packet2cf, Packet4f)

template<>
EIGEN_STRONG_INLINE Packet2cf
pdiv<Packet2cf>(const Packet2cf& a, const Packet2cf& b)
{
	// TODO optimize it for AltiVec
	Packet2cf res = pmul(a, pconj(b));
	Packet4f s = pmul<Packet4f>(b.v, b.v);
	return Packet2cf(pdiv(res.v, padd<Packet4f>(s, vec_perm(s, s, p16uc_COMPLEX32_REV))));
}

template<>
EIGEN_STRONG_INLINE Packet2cf
pcplxflip<Packet2cf>(const Packet2cf& x)
{
	return Packet2cf(vec_perm(x.v, x.v, p16uc_COMPLEX32_REV));
}

EIGEN_STRONG_INLINE void
ptranspose(PacketBlock<Packet2cf, 2>& kernel)
{
	Packet4f tmp = vec_perm(kernel.packet[0].v, kernel.packet[1].v, p16uc_TRANSPOSE64_HI);
	kernel.packet[1].v = vec_perm(kernel.packet[0].v, kernel.packet[1].v, p16uc_TRANSPOSE64_LO);
	kernel.packet[0].v = tmp;
}

template<>
EIGEN_STRONG_INLINE Packet2cf
pblend(const Selector<2>& ifPacket, const Packet2cf& thenPacket, const Packet2cf& elsePacket)
{
	Packet2cf result;
	result.v = reinterpret_cast<Packet4f>(
		pblend<Packet2d>(ifPacket, reinterpret_cast<Packet2d>(thenPacket.v), reinterpret_cast<Packet2d>(elsePacket.v)));
	return result;
}
#endif

} // end namespace internal

} // end namespace Eigen

#endif // EIGEN_COMPLEX32_ALTIVEC_H
